High Sinus, Lower Risk: A Paradigm Shift in Frontal Fracture Patterns.

OBJECTIVE: The morphology of the frontal sinus (FS) has long been debated as a determinant of fracture type and severity. This study aimed to evaluate the association between sinus dimensions, fracture patterns, and clinical outcomes using real-world data. STUDY DESIGN: Retrospective cohort study. SETTING: Tertiary trauma referral center. METHODS: We retrospectively reviewed the records of 48 frontal sinus fractures treated at a tertiary trauma center. Volumetric and dimensional measurements (volume, height, width, and anteroposterior depth) were obtained from CT scans. Each sinus was segmented and analyzed separately using 3D Slicer software. Sinuses were categorised according to cohort-derived percentiles and established classifications. Associations between sinus anatomy, fracture type, and outcomes were analyzed using logistic regression. RESULTS: While most sinus dimensions showed odds ratios greater than 1 for anterior table fractures, only the categorical analysis of sinus height demonstrated statistical significance. Cohort-based high sinuses (≥ 22.22 mm) were associated with isolated anterior table fractures (p = 0.014, OR = 4.83, 95% CI: 1.38-16.9). When comparing sinuses with larger volumes, a similar trend towards anterior-only fractures was observed, though not statistically significant. Patients with anterior-only fractures had fewer displaced fractures, shorter hospitalisation, and lower rates of intracranial haemorrhage and ICU admission. CONCLUSION: Frontal sinus height appears to be the most clinically relevant parameter influencing fracture patterns. Vertically expanded sinuses may act as protective "crumple zones," mitigating posterior table involvement and severe intracranial injury.